Cook cauliflower: In a pot with a steamer basket, steam cauliflower until very tender, 18 to 20 minutes. Drain. Cool slightly.
Cook quinoa: In a stockpot over high heat, bring water to a boil. Add quinoa. Stir. Return to boil. Reduce heat. Cover. Simmer until quinoa is tender and liquid is absorbed, 20 to 25 minutes. Fluff with fork. Cool slightly.
Preheat oven to 375 F.
In mixer bowl with paddle attachment, place steamed cauliflower, 1 cup cooked quinoa, mozzarella, first amount of panko bread crumbs, and egg whites. Mix on medium speed until cauliflower is coarsely mashed and mixture is well blended, 4 to 5 minutes.
On parchment-lined sheet pan coated with cooking spray, portion cauliflower mixture (about 1/2 cup for each cake) 2" apart.
Gently press each portion to form a 3 1/2" cake.
Combine second amount of Parmesan and second amount of panko bread crumbs. Toss to mix. Top each cake with 1 tablespoon Parmesan-panko mixture.
Bake until internal temperature reaches 160 F, 18 to 20 minutes. Cool 10 minutes before removing from parchment-lined pan.
To serve: Top 2 Cauliflower-Quinoa Cakes cake with 1/3 cup of hot Pomodoro Sauce.
Pomodoro Sauce
In saute pan or pot over medium-high heat, heat vegetable oil. Add garlic. Saute until aromatic, 30 seconds.
Add marinara or spaghetti sauce and water. Mix well. Bring to a boil. Reduce heat. Simmer 5 minutes. Stir in Roasted Grape Tomatoes. Heat through. At the time of service, stir in basil.
Notes
Roasted Grape Tomatoes: Toss 10 oz. fresh grape tomatoes with 2 teaspoons olive oil on a sheet pan. Roast in a preheated oven (375 F) until lightly browned, 12 to 15 minutes. Cool.